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1.
ACS Omega ; 8(22): 19674-19691, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37305322

RESUMO

Nowadays, antibiotic-loaded biomaterials have been widely used in wound healing applications. However, the use of natural extracts has come into prominence as an alternative to these antimicrobial agents in the recent period. Among natural sources, Cissus quadrangularis (CQ) herbal extract is used for treatment of bone and skin diseases in ayurvedic medicine due to its antibacterial and anti-inflammatory effects. In this study, chitosan-based bilayer wound dressings were fabricated with electrospinning and freeze-drying techniques. CQ extract-loaded chitosan nanofibers were coated on chitosan/POSS nanocomposite sponges using an electrospinning method. The bilayer sponge is designed to treat exudate wounds while mimicking the layered structure of skin tissue. Bilayer wound dressings were investigated with regard to the morphology and physical and mechanical properties. In addition, CQ release from bilayer wound dressings and in vitro bioactivity studies were performed to determine the effect of POSS nanoparticles and CQ extract loading on NIH/3T3 and HS2 cells. The morphology of nanofibers was investigated with SEM analysis. Physical characteristics of bilayer wound dressings were determined with FT-IR analysis, swelling study, open porosity determination, and mechanical test. The antimicrobial activity of CQ extract released from bilayer sponges was investigated with a disc diffusion method. Bilayer wound dressings' in vitro bioactivity was examined using cytotoxicity determination, wound healing assay, proliferation, and the secretion of biomarkers for skin tissue regeneration. The nanofiber layer diameter was obtained in the range of 77.9-97.4 nm. The water vapor permeability of the bilayer dressing was obtained as 4021 to 4609 g/m2day, as it is in the ideal range for wound repair. The release of the CQ extract over 4 days reached 78-80% cumulative release. The release media were found to be antibacterial against Gram-negative and Gram-positive bacteria. In vitro studies showed that both CQ extract and POSS incorporation induced cell proliferation as well as wound healing activity and collagen deposition. As a result, CQ-loaded bilayer CHI-POSS nanocomposites were found as a potential candidate for wound healing applications.

2.
ACS Omega ; 8(10): 9415-9422, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36936344

RESUMO

The effect of zinc borate (ZB) and high-molecular-weight siloxane (SIL) on flame retardancy, mechanical, and thermal properties of aliphatic polyketone (POK)-containing aluminum diethyl phosphinate (OF) was investigated in this study. Ten wt % OF is sufficient to obtain V0 rating according to the UL94 test. As the weight fraction of OF was increased, the flame retardancy properties and LOI values improved, while the tensile and impact properties decreased. To avoid the degradation in mechanical and impact properties as much as possible and obtain the same and better flame retardancy properties, synergists such as SIL and ZB were used. Flame retardancy of POK-based composites was determined by the limiting oxygen index (LOI) test, UL94 measurement, and cone calorimeter test. The additions of 1 wt % SIL and ZB have not led to a considerable decrease in the tensile strength and impact properties of POK-10OF. While ZB and SIL are very efficient in decreasing the smoke density, ZB is more efficient than SIL in increasing the LOI value of the composite. The addition of 1, 2, and 4 wt % ZB and SIL synergists did not lower their UL94 ratings. Moreover, it can be added that ZB is more efficient than SIL in decreasing the fire growth rate (FIGRA) and maximum average rate of heat emission (MARHE) values. Using OF (10 wt %) and ZB (4 wt %), LOI values higher than 32% and smoke density values lower than 150 were obtained.

3.
World Neurosurg ; 73(4): 326-33, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20849787

RESUMO

BACKGROUND: The significance of medial and lateral opticocarotid recesses and the planum sphenoidale region in skull base pathologies for the transsphenoidal-transplanum approach were evaluated. METHODS: The sphenoid bone block samples were extracted from adult cadavers. Dissections and measurements in the opticocarotid and planum sphenoidale regions were performed in 29 samples using a surgical microscope. For histologic evaluation, oblique sections through the bilateral opticocarotid regions were obtained and examined in eight samples. RESULTS: Optic, carotid prominences, and medial and lateral opticocarotid recesses can be identified as lateral markers intraoperatively to the extent of the exposure. The lateral opticocarotid recess was observed to be prominent in all samples. In all samples, the groove formed by optic and carotid prominences between the medial and lateral opticocarotid recesses was seen. This groove was designated the inter-recess sulcus. In the transsphenoidal-transplanum approach, the area needed for a reliable bone resection was measured as a mean of 237.32 ± 30.96 mm(2). The mean angle between optic nerves was 115.41 ± 18.39 degrees. The mean anteroposterior length of the planum sphenoidale was 14.84 ± 1.52 mm. In histologic sections, collagenous ligaments between the anterior part of cavernous sinus and the adventitia layer of internal carotid artery were more frequent and regular than the inferior part of optic nerve. CONCLUSIONS: The lateral opticocarotid recess is a reliable and persistent indicator for extended transsphenoidal surgery. To approach the opticocarotid region near the internal carotid artery and optic nerve, a careful dissection is needed to minimize surgical injuries to the optic nerve and carotid artery. Other factors determining a reliable bone resection are the anteroposterior length of the planum sphenoidale and the distance and width of the angle between optic nerves. Attention should be given to individual anatomic variations of the region when planning and performing transsphenoidal-transplanum surgery.


Assuntos
Fossa Craniana Anterior/cirurgia , Fossa Craniana Média/cirurgia , Endoscopia/métodos , Cavidade Nasal/cirurgia , Procedimentos Neurocirúrgicos/métodos , Osso Esfenoide/cirurgia , Cadáver , Artéria Carótida Interna/anatomia & histologia , Artéria Carótida Interna/cirurgia , Fossa Craniana Anterior/anatomia & histologia , Fossa Craniana Média/anatomia & histologia , Craniotomia/métodos , Dissecação/métodos , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/prevenção & controle , Masculino , Microcirurgia/instrumentação , Microcirurgia/métodos , Cavidade Nasal/anatomia & histologia , Procedimentos Neurocirúrgicos/instrumentação , Nervo Óptico/anatomia & histologia , Nervo Óptico/cirurgia , Sela Túrcica/anatomia & histologia , Sela Túrcica/cirurgia , Neoplasias da Base do Crânio/cirurgia , Osso Esfenoide/anatomia & histologia
4.
World J Gastroenterol ; 16(20): 2537-41, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20503454

RESUMO

AIM: To investigate the efficiency of levobupivacaine in treating experimentally induced colitis in rats. METHODS: Colitis was induced by trinitrobenzene sulfonic acid and ethanol in 30 rats under general anesthesia, and 10 rats were used as a sham group. Subsequent to induction of colitis, rats were divided into three groups; budesonide group received 0.1 mg/kg budesonide, levobupivacaine group received 10 mg/kg levobupivacaine and saline group received 1 mL saline solution via rectal route for 7 d. In the sham group, only routine rectal catheterization was performed without use of any material. At the end of 7 d, laparotomy and total colectomy were performed for histopathological examination in all rats and blood samples were drawn for measurement of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 following cardiac puncture. Macroscopic and microscopic evaluations of the specimens were performed by a pathologist blinded to group assignment of the rats. RESULTS: Weight loss (P = 0.016) and macroscopic examination scores (P = 0.001) were significantly higher in saline group than others. Histopathological scoring was comparable between all colitis groups (P = 0.350). There was no significant difference in TNF-alpha levels and IL-6 levels (P = 0.150). CONCLUSION: The significant improvement in macroscopic scores suggests that levobupivacaine may have topical anti-inflammatory effects in an experimental colitis model; however, this finding was not supported by microscopic findings.


Assuntos
Anestésicos Locais/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Animais , Budesonida/uso terapêutico , Bupivacaína/análogos & derivados , Bupivacaína/uso terapêutico , Modelos Animais de Doenças , Levobupivacaína , Masculino , Ratos , Ratos Sprague-Dawley
6.
J Interferon Cytokine Res ; 30(6): 433-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20307202

RESUMO

The aim of this study is to investigate the immunoregulatory role of interleukin-12 and interferon-gamma in children with chronic hepatitis B who are treated with interferon-alpha therapy. The patients were divided into 2 groups: Group I included 16 children with naive chronic replicative hepatitis B infection, and Group II included 6 children who are inactive hepatitis B virus (HBV) carriers. Group I received interferon-alpha subcutaneously (10 mU/m(2)/dose), 3 times a week during 4 months. Initial serum alanine aminotransferase (ALT) levels, hepatitis B serologic markers, serum interleukin-12 and interferon-gamma levels were measured. In Group I, laboratory tests were re-evaluated in the second and fourth months. Liver biopsy was performed in all patients and samples were used for tissue interleukin-12 level evaluation and histopathological examination. Hepatic activity index (HAI) and serum interferon-gamma were significantly higher in Group I (P < 0.05). Initial tissue interleukin-12 levels in Group I were low but a significant increase was observed at the fourth month (P < 0.05). While responder patients in Group I had marked elevation of tissue interleukin-12 levels, nonresponders did not reveal considerable changes at the fourth month evaluation. A negative correlation was found between serum HBV-DNA copies and interferon-gamma levels prior to therapy (P < 0.01, r: -0.66). The analysis of cytokine levels with serum transaminases demonstrated a positive correlation between the tissue interleukin-12 levels at the fourth month and serum ALT levels at the beginning and second month of the therapy (r: 0.77, P < 0.05 and r: 0.92, P < 0.05, respectively). This is the first study emphasizing the relationship between tissue cytokine levels and therapy success. Understanding the course of chronic hepatits B in the pediatric population will help us to clarify some debates on the treatment.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatite B Crônica/diagnóstico , Imunoterapia , Interferon-alfa/administração & dosagem , Interleucina-12/metabolismo , Fígado/metabolismo , Adolescente , Criança , DNA Viral/sangue , Feminino , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Humanos , Injeções Subcutâneas , Interferon-alfa/uso terapêutico , Interferon gama/sangue , Interferon gama/imunologia , Interleucina-12/imunologia , Fígado/imunologia , Fígado/virologia , Masculino , Prognóstico , Estudos Prospectivos , Resultado do Tratamento , Replicação Viral/efeitos dos fármacos , Replicação Viral/imunologia
7.
Heart Surg Forum ; 13(1): E28-30, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20150036

RESUMO

Primary sarcoma of the pulmonary artery (PSPA) is an extremely rare tumor of the cardiovascular system. The prognosis is very poor. The clinical symptoms and imaging findings imitate those of pulmonary emboli, causing delays in diagnosis. In this case report, we describe a 73-year-old man with PSPA who initially was admitted with exertional shortness of breath. Transthoracic echocardiographic evaluation revealed 2 masses in the pulmonary artery causing pulmonary hypertension. The patient underwent operation, but he could not be weaned off cardiopulmonary bypass at the end of the operation and died. Pathologic examination of the masses revealed pulmonary sarcoma. Although this patient was admitted to our clinic only 2 weeks after the initial symptoms, he already had distal metastases.


Assuntos
Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/cirurgia , Artéria Pulmonar/cirurgia , Sarcoma/complicações , Sarcoma/cirurgia , Neoplasias Vasculares/complicações , Neoplasias Vasculares/cirurgia , Idoso , Evolução Fatal , Humanos , Masculino
8.
Clin Anat ; 22(8): 916-24, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19806669

RESUMO

Neuroanatomical structures that form the floor of the third ventricle (FTV) and neighboring tissues are important in the context of third ventriculostomy (TV) procedures. Thorough knowledge of the anatomical and histological organization of the region would be useful in understanding and preventing surgical complications. Taking the third ventricle region as a model, we aimed to simulate TV and make measurements of 23 cadaver brains, as well as perform histological examinations of the third ventricular floor on five cadaver brains. During the endoscopic TV, we examined the degree to which the structures surrounding the FTV were affected by surgical simulation. To make a clinical comparison, the distance between the center of the FTV and the basilar apex was measured on cranial magnetic resonance images (MRIs) of 15 subjects with normal ventricular systems and 15 subjects with moderately enlarged ventricles. Histological examination revealed that the ependymal cells and arachnoid membrane formed the inner and outer surfaces of the third ventricle floor, respectively, whereas the stroma was made up of glial cells exclusively. This region was gliotic and avascular. When cadaver brains with normal and hydrocephalic ventricles were compared, there were significant differences in the distance between the center of the floor and the basilar apex (P < 0.001). On the basis of our study, the optimal site for TV fenestration and balloon inflation is just anterior to the mamillary bodies to avoid injury to neighboring structures.


Assuntos
Endoscopia/métodos , Terceiro Ventrículo/patologia , Terceiro Ventrículo/cirurgia , Ventriculostomia/métodos , Cadáver , Humanos , Hidrocefalia/patologia , Imageamento por Ressonância Magnética
9.
Clin Biochem ; 42(9): 802-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19217891

RESUMO

OBJECTIVES: Levels of soluble receptor for advanced glycation endproducts (sRAGE) have been linked to several components of the metabolic syndrome. We tested the hypothesis that plasma levels of sRAGE may be associated with non-alcoholic fatty liver disease. DESIGN AND METHODS: We enrolled subjects with definite nonalcoholic steatohepatitis (NASH, n=40), borderline NASH (n=8), simple fatty liver (n=9) and healthy controls (n=14). Plasma levels of sRAGE were measured by ELISA. RESULTS: Concentrations of sRAGE were significantly lower in patients with definite NASH (1080+/-392 pg/mL, P<0.01) and borderline NASH (1050+/-278 pg/mL, P<0.05) compared to controls (1480+/-387 pg/mL). Levels of sRAGE were significantly and inversely correlated with ALT (r=-0.30, P<0.05) and AST (r=-0.23, P<0.05). CONCLUSION: Plasma levels of sRAGE are significantly reduced in definite and borderline NASH.


Assuntos
Fígado Gorduroso/sangue , Receptores Imunológicos/sangue , Adulto , Ensaio de Imunoadsorção Enzimática , Humanos , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada
10.
Int Ophthalmol ; 29(1): 57-60, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18008054

RESUMO

In this report, we describe three adult patients diagnosed with lacrimal sac pyogenic granuloma. The presenting symptoms were acute dacryocystitis, lacrimal mass, and bloody tears. The nasolacrimal drainage pathway was obstructed in all cases. Radiologic evaluation performed in one patient revealed the presence of a well-defined mass in the sac with homogenous contrast uptake. Histopathologic examination revealed capillary proliferation and inflammatory cells in a fibromyxoid stroma. The patients were followed up for 11-23 months after external dacryocystorhinostomy without recurrence of the tumor or nasolacrimal obstruction. Pyogenic granuloma may develop from the lacrimal sac mucosa and may cause bloody epiphora. Such a tumor is visualized as a hemorrhagic mass lesion, and it may not have a negative effect on the outcome of DCR.


Assuntos
Granuloma Piogênico/patologia , Doenças do Aparelho Lacrimal/patologia , Adulto , Dacriocistorinostomia , Feminino , Granuloma Piogênico/diagnóstico por imagem , Humanos , Doenças do Aparelho Lacrimal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ducto Nasolacrimal/patologia , Radiografia , Ultrassonografia
11.
Neurosurg Rev ; 31(1): 91-8; discussion 98-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17932696

RESUMO

Pituitary adenomas extend to the suprasellar region via diaphragmal passage and extend to the cavernous sinus via the medial wall (MW). Better understanding of the dynamics of suprasellar and parasellar extension of sellar region pathologies requires microanatomical comparison of diaphragma sellae (DS) and the MW of the cavernous sinus. This study provides the first detailed quantitative assessment between DS and MW of the cavernous sinus. Microanatomical details and histopathological examinations of the DS and MWs of the cavernous sinus were studied in sphenoid block samples obtained from adult cadavers, and the thicknesses of the DS and the MW of the cavernous sinus were measured. Mean thickness of the DS was 216.73 +/- 51.26 microm in the center and 367.33+/-133.66 microm in the periphery. Mean thickness of the lower third of the MW was 161.53+/-53.86 microm and that of the upper third was 278.46+/-162.79 microm. Difference between the thicknesses of the upper and lower thirds was significant (P<0.001). When the central thickness of the DS and lower third of the MW were compared, a significant difference was found (P<0.01). Our measurements suggest that when the DS is thick and the stalk opening is complete, the thickness of the lower third of the medial wall could be the major determinant of parasellar extension.


Assuntos
Adenoma/patologia , Neoplasias Hipofisárias/patologia , Sela Túrcica/patologia , Adulto , Antropometria , Seio Cavernoso/patologia , Humanos , Sela Túrcica/anatomia & histologia
12.
World J Gastroenterol ; 13(6): 837-44, 2007 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-17352011

RESUMO

AIM: To investigate whether serum levels of two soluble forms of extracellular cytokeratin 18 (M30-antigen and M65-antigen) may differentiate nonalcoholic steatohepatitis (NASH) from simple steatosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 83 patients with suspected NAFLD and 49 healthy volunteers were investigated. Patients with suspected NAFLD were classified according to their liver histology into four groups: definitive NASH (n=45), borderline NASH (n=24), simple fatty liver (n=9), and normal tissue (n=5). Serum levels of caspase-3 generated cytokeratin-18 fragments (M30-antigen) and total cytokeratin-18 (M65-antigen) were determined by ELISA. RESULTS: Levels of M30-antigen and M65-antigen were significantly higher in patients with definitive NASH compared to the other groups. An abnormal value (> 121.60 IU/L) of M30-antigen yielded a 60.0% sensitivity and a 97.4% specificity for the diagnosis of NASH. Sensitivity and specificity of an abnormal M65-antigen level (> 243.82 IU/L) for the diagnosis of NASH were 68.9% and 81.6%, respectively. Among patients with NAFLD, M30-antigen and M65-antigen levels distinguished between advanced fibrosis and early-stage fibrosis with a sensitivity of 64.7% and 70.6%, and a specificity of 77.3% and 71.2%, respectively. CONCLUSION: Serum levels of M30-antigen and M65-antigen may be of clinical usefulness to identify patients with NASH. Further studies are mandatory to better assess the role of these apoptonecrotic biomarkers in NAFLD pathophysiology.


Assuntos
Fígado Gorduroso/sangue , Fígado Gorduroso/diagnóstico , Hepatite/sangue , Hepatite/diagnóstico , Queratina-18/sangue , Adulto , Idoso , Biomarcadores/sangue , Diagnóstico Diferencial , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Transaminases/sangue , Ultrassonografia
13.
Neurol Med Chir (Tokyo) ; 46(3): 157-60, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16565587

RESUMO

Spinal extradural angiolipomas are benign tumors mostly localized in the thoracic region. A 50-year-old woman and a 36-year-old man presented with rare lumbar spinal angiolipoma manifesting as low back pain but without neurological signs. Magnetic resonance imaging showed lumbar extradural tumors at the L4-5 and L1-2 levels, respectively. Each patient underwent complete surgical resection of the epidural tumors. Histological examination revealed characteristics of angiolipomas in both tumors. The symptoms of both patients improved postoperatively and no recurrence of the tumors was found 1 year after surgery.


Assuntos
Angiolipoma/patologia , Angiolipoma/cirurgia , Vértebras Lombares , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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